This invention relates to an apparatus for X-ray fluoroscopy and fluorography comprising a main frame which is provided with X-ray radiating and detecting means and supported by a base so as to be movable vertically and rotatable around a horizontal axis, as well as a top board disposed between the X-ray radiating and detecting means.
Apparatus of this type, having an X-ray tube above the top board for placing the target subject thereon, have been disclosed, for example, in Japanese Patent Publication Tokkai 6-30920. FIG. 7 shows an apparatus 100 of this kind, having a base 101 set on a floor, a frame 102 which is vertically movable with respect to it, and a main body frame 103 which is supported by the movable frame 102 rotatably around an axis P.sub.11. An X-ray radiating device 104 and an image intensifier 105 are attached to the main body frame 103 opposite to each other, and a top board 106 is attached to the main body frame 103 so as to be between the X-ray radiating device 104 and the image intensifier 105. When a target subject is to be placed on the top board 106, the main body frame 103, to which is attached the top board 106, is lowered such that the positioning of the target subject thereon can be effected easily.
A prior art apparatus thus structured is disadvantageous in that its front-to-back dimension L is large because both a rotary mechanism 107 for rotation around the axis of rotation P.sub.11 and the vertically movable frame 102 are disposed next to each other at the back side of the apparatus (that is, the right-hand side in FIG. 7). This means that the apparatus as a whole cannot be made compact.